Prevalence and associated factors of TB and HIV coinfections among adult inmates with presumptive pulmonary TB in a Kenyan prison.

BACKGROUND: Tuberculosis (TB) is more than ten times higher in prisons compared to the general population, and HIV-infected persons are at increased risk of developing active TB and death. In the World Health Organization (WHO) African region, however, where the TB and HIV coinfections are highest, and prisons rarely factored in national disease surveillance, epidemiological data to inform TB control interventions in correctional facilities is limited. In this study, we assessed the prevalence of TB and HIV coinfections, as well as the factors associated with coinfections in our study setting. METHODS: This was a prospective cross-sectional study among 157 adult (≥ 18 years) prisoners presenting with symptoms of pulmonary TB at Shimo La Tewa Prison, Kenya, between January and June 2023. The study excluded those with a history of anti-TB drugs use or on treatment follow-up and collected demographic and clinical characteristics data using a questionnaire. Sputum samples were collected and processed immediately using Xpert® MTB/RIF assay or stored at 4 °C for three (3) days in case of delay. RESULTS: The overall prevalence of TB among inmates with presumptive pulmonary TB was 10.2%, 95% CI 6.37-16.91% (16/157), HIV 19.1%, 95% CI 13.73-25.97% (30/157). All the TB cases were positive for HIV (16/16, 100%), translating to TB/HIV coinfection of 10.2%, 95% CI 6.37-16.91% (16/157), and there was no rifampicin resistance. TB and HIV coinfection cases were found among underweight (100%, 16/16) prisoners. The independent factors associated with TB and HIV coinfections were education level (adjusted OR = 0.17, p = 0.007), smoking history (adjusted OR = 3.01, p = 0.009) and illegal drug use history (adjusted OR = 4.55, p = 0.044). CONCLUSION: We report a high prevalence of pulmonary TB and HIV coinfections among adult inmates with presumptive pulmonary TB in Kenya, with education level, smoking status, and illegal drug use as the independent factors associated with the coinfection. The authority should take measures to protect HIV-positive prisoners from TB, focusing on education, nutrition, smoking, and illegal drug use.

Arboviruses and Blood Meal Sources in Zoophilic Mosquitoes at Human-Wildlife Interfaces in Kenya.

Background: Zoophilic mosquitoes play an important role in the transmission of arboviruses of medical importance at human-wildlife interfaces, yet arbovirus surveillance efforts have been focused mostly on anthropophilic mosquitoes. Understanding the diversity of zoophilic mosquitoes and their associated feeding patterns and arboviruses can inform better vector control strategies. Materials and Methods: We morphologically identified mosquitoes collected from two game reserves in Kenya, the Maasai Mara National Reserve (MMNR) and locations near the Shimba Hills National Reserve (SHNR). Representative mosquitoes were also identified by cytochrome c oxidase subunit 1 (COI) barcode sequencing. In addition, we identified the vertebrate hosts of mosquito blood meals from the contents of each mosquito's abdomen by high-resolution melting (HRM) analysis and sequencing of COI, 16S ribosomal RNA, and cytochrome b gene PCR products. Similarly, mosquito arbovirus infections were identified by HRM analysis and sequencing of Alphavirus- and Flavivirus-specific RT-PCR products. Results: Of 2858 mosquitoes collected, 51 were engorged with blood meals from seven different vertebrate hosts, including humans, birds, domestic, and peridomestic animals and wildlife. Culex was the most abundant mosquito genus, with Culex pipiens being the most abundant species in both study regions. Among MMNR samples, we detected dengue serotype-2 virus (DENV-2) for the first time in Aedes tarsalis and Aedes tricholabis, as well as Sindbis virus in male Cx. pipiens. We also detected DENV-2 in Aedes aegypti sampled from locations near the SHNR. Human and diverse wildlife blood meals were identified, including bushbuck blood in the dengue-infected Ae. tarsalis and both human and hippopotamus blood in a single Eretmapodites chrysogaster mosquito. Conclusions: Our findings highlight the potential risk of sylvatic dengue and Sindbis transmission to humans by zoophilic mosquitoes at human-wildlife interfaces in Africa. Of specific importance, we provide evidence of sylvatic DENV-2 in Ae. tarsalis and Ae. tricholabis, representing potential new dengue vectors.

Rectal gonorrhoea and chlamydia among men who have sex with men in coastal Kenya.

Background: Men who have sex with men (MSM) have a higher prevalence of Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) infections compared to the rest of the population, often remaining undiagnosed. In Kenya, prevalence of rectal CT and NG infection and NG antimicrobial sensitivity are poorly described. Methods: MSM who reported receptive anal intercourse (RAI) were recruited from an ongoing human immunodeficiency virus acquisition and treatment study in coastal Kenya in 2016-2017. Rectal swabs were collected at two time points 6 months apart to estimate prevalence and incidence of CT/NG infection using a molecular point-of-care assay. Participants positive for CT or NG were treated according to national guidelines. NG culture and antimicrobial susceptibility testing was performed. Participant and risk behaviour characteristics were collected and association with baseline CT/NG prevalence assessed by multivariable regression analysis. Results: Prevalence of CT/NG in 104 MSM was 21.2% (CT 13.5%, NG 9.6%, dual infection 1.9%) at baseline and 25.9% in 81 MSM at follow-up (CT 14.8%, NG 14.8%, dual infection 3.7%). CT/NG incidence was estimated at 53.0 (95% CI, 34.5-81.3) per 100 person-years. Most CT/NG positive participants were asymptomatic: 95.5% at baseline and 100% at follow-up. CT/NG infection was associated with being paid for sex [adjusted odds ratio (aOR)=6.2, 95% CI (1.7-22.9)] and being in formal employment [aOR=7.5, 95% CI (1.1-49.2)]. Six NG isolates were obtained at follow-up; all were susceptible to ceftriaxone and cefixime and all were resistant to penicillin, tetracycline and ciprofloxacin. Conclusions: There is a high prevalence and incidence of asymptomatic rectal CT and NG in MSM reporting RAI in coastal Kenya. MSM who were paid for sex or had formal employment were more likely to be infected with CT/NG suggesting increased risk behaviour during transactional sex. Antimicrobial susceptibility results suggest that current antibiotic choices in Kenya are appropriate for NG treatment.